Sooooo you’re taking advice from an 132 year old book?....yeah makes senseHere:
"If at first they should get a little raw or rubbed, a few
applications of weak tannic acid solution, or rosin, or good
strong pickle out of the salt-pork barrel, will soon make the
hands and knuckles tough."
- Billy Edwards' "Art of Boxing and Manual of Training" from 1888